Minnesota's Longest Cave Is Part Of A Scenic State Park With Camping, Fishing, And Trails

Minnesota may be known as the Land of 10,000 Lakes, but perhaps it should be just as well-known for its hundreds of caves. A layer of limestone and dolostone created a "karst landscape" beneath the state's southeastern corner, which led to the formation of caves and underground streams. As a result, there are lots of caves to explore in Minnesota, including at Forestville/Mystery Cave State Park, a scenic refuge in Preston that also offers hiking, fishing, and camping.

Located about a two-hour drive southeast of Minneapolis, not far from the border of Iowa, the state park is home to Mystery Cave, discovered in 1937. With more than 13 miles of subterranean passages leading past stalactites, stalagmites, and aquamarine-hued underground pools, it's the longest cave in Minnesota. 

From May to October, you can see it on a guided hourlong tour ($15 for adults and $10 for kids, plus taxes and fees). More adventurous travelers can try the Wild Caving Tour ($80 plus taxes and fees), which involves crawling and climbing through cave passages. Reservations for both are available online.

Above ground, Forestville/Mystery Cave State Park has plenty more natural attractions to offer visitors. The densely forested park features 20 miles of hiking trails that lead through scenic landscapes. For an easy outing, try the nearly mile-long Big Spring Loop, which offers peaceful views over the South Branch Root River. The hike takes less than an hour to complete. 

The more challenging 4.5-mile Overlook, Sugar Camp Hallow, Cemetery, and River Bottom Loop passes some of the park's historic landmarks, including cemeteries and schoolhouses (part of Forestville, a restored late-19th-century village), and continues to an elevated lookout point with beautiful views over the surrounding forest. Past hikers say it's especially breathtaking in autumn, when the trees' leaves change red, yellow, and orange. For more gorgeous fall foliage in the region, don't miss the small towns of southeastern Minnesota's scenic Root River Valley. 

If you're looking to cast a line for brown trout, there's excellent fishing at a trio of streams that run through the park. The regular season lasts from mid-April to mid-September, and outside of that time frame, only catch-and-release fishing is allowed. You'll need a fishing license with a trout stamp to participate, and you can apply for one online. 

Whether you go to Forestville/Mystery Cave State Park to explore its fascinating cave system, hike on wooded trails, or catch trout, you can stay overnight in the park year-round. The main campground, open seasonally, has 73 sites ($25 per night, plus fees) with access to showers and flush toilets. When the weather cools off, book one of the park's rustic camper cabins ($90 per night, plus fees) with heat and electricity, but without indoor plumbing. Each sleeps five or six people and comes with an outdoor picnic table and fire ring. Reservations can be made online. 

The state park is open daily from  8 a.m. until 10 p.m., and ranger station hours vary slightly according to the season. All day-use visitors and campers pay a $7 fee (per vehicle) to enter the park. Note that there's no cell phone service in the park, but you can access Wi-Fi at the William J. Morrissey Visitor Center at Mystery Cave, located near the cave's entrance. Pick up picnic and grilling supplies at Preston Foods in the nearby town of Preston. 

If you love the experience of exploring Minnesota's longest cave, consider a detour to Jewel Cave National Monument, one of the world's longest caves, a hidden-away gem in South Dakota, or if you're looking for more fishing, visit Rainy Lake, Minnesota's fishing lake and a gateway to Voyageurs National Park, located in the state's north.